This invention generally relates to a memory mechanism and more particularly, to a memory mechanism which is adapted incrementally change or eliminate selected information of a plurality of informations each including a plurality of incremental informations whenever the informations in the one or more information systems are desired to be incrementally changed.
In a digital clock, for example, when the day and month indications are to be changed in increment, it is only necessary that the day indications ranging from the first day to the thirty-first day and the month indications ranging from January to December are cyclically repeated. However, the number of days of the month varies one month after another, that is, January has thirty-one days, February has twenty-eight or nine days, March has thirty-one days and April has thirty days, respectively, for example and thus, if the incremental month indication change cycle is merely related to the incremental day indication change cycle in such a manner that the month indication is changed by one increment at the end of the thirty-first day of the preceding month, there will be the delay time of three or two days if the month indication is changed from that of February to that of March, for example. And there will be also the delay time of one day when the month indication is incrementally changed from the indication of April to that of May. Thus, error will occur when the day and month indications are changed. In order to eliminate such error in changing the day and month indications when the month indication is changed in increment from that of an even month to that of the succeeding odd month, it is necessary that the month indication change is effected by skipping the day indications corresponding to the difference in number of days between the consecutive two months. As one example of the memory mechanisms for controlling the date indication change, the gear mechanism which utilizes the differential gear feeding has been developed by Solari & C.U. in Italy. However, the prior art memory mechanism has the disadvantages that the mechanism has a complicated construction and encounters difficulty in controlling incremental date change and adjustment.